Field of the Disclosure
The present disclosure relates generally to pharmaceutical compositions, and more particularly, to natural solubilizer agents within transdermal pharmaceutical compositions for the delivery of hormones.
Background Information
The delivery of active pharmaceutical ingredients s (APIs) through a biological surface (e.g., skin tissue) is a well-recognized method of treatment for controlled drug delivery. Such APIs are delivered to the surface of the skin of a patient with transdermal delivery through the skin occurring thereafter.
Transdermal drug delivery is receiving increased attention due to the ability of an administration regime to provide a controlled route for the release of an API into the systemic circulation of the patient. The delivery of drugs (e.g., hormones) using transdermal methodology provides many benefits as compared to other delivery methods, such as, for example topical, oral, injection, and the like. Primarily, transdermal delivery is a comfortable, convenient and noninvasive way of administering drugs. Issues with other drug delivery methods include, for example, the variable rates of absorption of APIs in each metabolism encountered when using oral treatments (e.g., in oral hormones), and other inherent inconveniences, such as, gastrointestinal irritation.
Transdermal delivery is a particularly advantageous delivery route. It is a non-invasive drug delivery method with the benefits of better patient compliance, less risk of infection, and lower cost than invasive procedures such as injection and implantation. Transdermal delivery also provides a much shorter onset time (i.e., the time from administration to therapeutic effect) than oral delivery does. Transdermal applications of APIs are simple and can be administered by a caregiver or the patient with minimal discomfort.
Some APIs, such as, hormones (e.g., estrogens, androgens, and other sex hormones), are derived from a kind of fat called cholesterol. Their lipid-based origin makes hormones fat or lipid soluble, but prevents hormones from freely dissolving in water (water insoluble). Since blood plasma (the liquid part of blood that carries hormones to tissues and cells throughout the body) is about 90 percent water, hormones have trouble in mixing with and traveling into the blood. When using transdermal applications for the delivery of hormones, it is difficult to obtain desired treatment outcomes with preferred dosage levels of hormones because of the relatively lower water solubility and lower skin permeation properties. Transdermal application formulations including hormones require high loads of hormones or large application surface areas in order to provide desired hormone levels in the blood.
The lower solubility and relatively lower permeability of many APIs with diverse physicochemical characteristics can be improved using chemical enhancement means. Issues with most known chemical solubilizers and penetration enhancers include, for example, that they are often toxic, irritating, or allergenic. Improving APIs solubility may result in the decrease or elimination of penetration enhancers and thereby result in APIs becoming more available, and hence, more effective for a given dose.
Accordingly, there is a need for solubilizer agents in transdermal pharmaceutical compositions for hormone delivery, which can improve solubilization of hormones, thereby increasing skin permeation.